The biggest problem I found that was that neither headset was truly immersive. When wearing either one of the headsets, it felt like I was just looking at a really small television screen. The composite display still looked like a rectangular screen that easily fit inside my field of view. As a result, I still felt the same separation from the action of the game that I feel when playing on a regular television screen.
There is only one experience that I have found to generate a satisfactory feeling of being close to the action: an IMAX-Dome theater. A large-screen IMAX theater is so immersive that the visuals of a movie trick the viewer into thinking that the entire theater is moving. The reason for this is that the movie screen covers the spectator's entire field of view, including the viewer's peripheral vision, with a single unbroken image. A head mounted display should also be able to generate this kind of effect.
A problem with one of the displays I looked at was its lack of clarity. That system attempted to create a 3-D image by transforming the input feed from a game designed for normal 2-D screens into a pair of quickly alternating images that could be used by the glasses to create a 3-D image. They had a display of the modified input on display on a regular TV screen to demonstrate how it worked. However, this approach did not create a very clear image. Part of it had to be a goof on their part, since the text and UI of the game was not split into the two images. While it was readable on the TV display, it was constantly out-of-focus on the 3-D headset. However, the strobe-like alternation of images was discernible while wearing the headset. So, trying to make out any detail at all was difficult.
However, the 3-D display at the Intel booth did not do a particularly good job of creating a 3-D image at all. Perhaps it was just a poor choice of game, but I did not perceive much of a 30D effect while playing with their headset on. While I could read the UI and game text just fine, and there were no problems with clarity, the game just didn't feel like any different of an experience from watching it on a TV screen.
3-D can be a very difficult effect to achieve. However, I actually think immersion is not only easier to achieve than 3-D, but possible more rewarding. The feeling that the entire room around you is moving is a very strong effect that can really draw a player into a game. And it can simply be a matter of having a sufficiently high resolution headset that can cover the player's entire field of view. Trying to create a 3-D effect requires significantly greater engineering.
However, whether they are 3-D, immersive, or not, headsets could be a very interesting way of redefining the world of video-gaming. However, I will save that discussion for next time.